Preparation of 1,1,1,4,4,4-hexafluorobutane

Abstract

PCT No. PCT/JP92/01529 Sec. 371 Date Jul. 20, 1993 Sec. 102(e) Date Jul. 20, 1993 PCT Filed Nov. 24, 1992 PCT Pub. No. WO93/10067 PCT Pub. Date May 27, 1993.1,1,1,4,4,4-Hexafluorobutane is prepared by reducing 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 with hydrogen in the presence of a hydrogenation catalyst containing an alloy which contains at least one first metal component selected from the group consisting of platinum and palladium and at least one second metal component selected from the group consisting of silver, copper, gold, tellurium, zinc, chromium, molybdenum and thallium. 1,1,1,4,4,4-Hexafluorobutane can be prepared in a high selectivity and a high yield.

What is claimed is: 
     
       1. A method for preparing 1,1,1,4,4,4-hexafluorobutane comprising reducing 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 with hydrogen in the presence of a hydrogenation catalyst comprising an alloy which comprises at least one first metal component selected from the group consisting of platinum and palladium and at least one second metal component selected from the group consisting of silver, gold, tellurium, zinc, chromium, molybdenum and thallium. 
     
     
       2. The method according to claim 1, wherein 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 is prepared by fluorinating hexachloro-1,3-butadiene in a liquid phase in the presence of antimony chloro-fluoride and hydrogen fluoride. 
     
     
       3. The method according to claim 1, wherein said first metal component is platinum. 
     
     
       4. The method according to claim 3, wherein said second metal component is silver. 
     
     
       5. The method according to claim 3, wherein said second metal component is tellurium. 
     
     
       6. The method according to claim 3, wherein said second metal component is gold. 
     
     
       7. The method according to claim 3, wherein said second metal component is zinc. 
     
     
       8. The method according to claim 3, wherein said second metal component is chromium. 
     
     
       9. The method according to claim 3, wherein said second metal component is thallium. 
     
     
       10. The method according to claim 3, wherein said second metal component is molybdenum. 
     
     
       11. The method according to claim 1, wherein said alloy comprises 0.01 to 500 parts by weight of said second metal component per 100 parts by weight of said first metal component. 
     
     
       12. The method according to claim 11, wherein said alloy is present at a concentration of 0.05 to 5% by weight of a carrier for said catalyst. 
     
     
       13. The method according to claim 1, wherein the molar ratio of hydrogen to 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 is 2:1 or greater. 
     
     
       14. The method according to claim 13, wherein the molar ratio of hydrogen to 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 is 2:1. 
     
     
       15. The method according to claim 2, wherein said fluorination is conducted at a reaction temperature between 50° and 150° C. and at a constant reaction pressure between 3 and 30 kg/cm 2 .